The present invention relates to a chuck for clamping workpieces or tools, and includes a chuck body and at least two clamping jaws that are radially displaceably guided in the chuck body and are operable, via wedge surfaces, by a driven chuck piston that is axially displaceable.
A number of such chucks are known; see, for example, DE-PS 29 03 904, and DE-AS 1 301 689. The wedge surfaces needed for driving the chuck via the chuck piston are generally embodied as so-called key hooks that are provided on the radially inner end of the clamping jaws and engage in corresponding keyways of the chuck piston, which is axially displaceable in a central bore of the chuck body. Although such chucks give satisfactory results, they are subjected to deformations due to the influence of centrifugal force if the chuck is operated at very high speeds.
It is therefore an object of the present invention to provide a chuck of the aforementioned general type that while having a compact construction also has a very inherent stability and stiff construction in order not to be sensitive to the influence of centrifugal force that occurs at high speeds. Furthermore, while keeping the overall axial length as short as possible, it should be possible to provide the chuck with very small outer diameters and yet provide a large central bore, especially for the introduction of workpieces or tools.